KR101814850B1 - Aromatic hydrocarbon production process - Google Patents

Abstract

In this method for producing aromatic hydrocarbons, a raw material oil containing hydrotreated oil of pyrolytic crude oil obtained from an ethylene production apparatus is contacted with a catalyst for producing monocyclic aromatic hydrocarbons containing crystalline aluminosilicate to produce aromatic hydrocarbons for producing aromatic hydrocarbons Method. As the raw material oil, those having an end point of distillation phase of 400 DEG C or lower are used. The contact between the raw oil and the catalyst for producing monocyclic aromatic hydrocarbons is carried out at a pressure of 0.1 MPaG to 1.5 MPaG.

Description

AROMATIC HYDROCARBON PRODUCTION PROCESS [0002]

The present invention relates to a process for the production of aromatic hydrocarbons.

The present application claims priority based on Japanese Patent Application No. 2010-205666 filed on September 14, 2010, the contents of which are incorporated herein by reference.

A light cycle oil (hereinafter referred to as "LCO"), which is a decomposed light oil produced in a fluid catalytic cracking (hereinafter referred to as "FCC") apparatus, contains a large amount of polycyclic aromatic components and has been mainly used as a light oil / . In recent years, it has recently been proposed to use monocyclic aromatic hydrocarbons having 6 to 8 carbon atoms (for example, benzene, toluene, and xylenes (such as ethylbenzene and the like) having high added value, which can be used as raw materials for high octane gasoline base materials and petrochemical raw materials, A small amount of xylene), hereinafter referred to as " BTX ").

As a method for producing BTX from a polycyclic aromatic component, for example, the following method is known.

(1) A method of hydrocracking a hydrocarbon containing a polycyclic aromatic component in one stage (Patent Documents 1 and 2).

(2) Hydrogenation of a hydrocarbon containing a polycyclic aromatic moiety at the former stage followed by hydrocracking at the latter stage (Patent Documents 3 to 5).

(3) a method of directly converting hydrocarbons containing polycyclic aromatic components into BTX using a zeolite catalyst (Patent Document 6).

(4) A method of converting a mixture of hydrocarbons containing a polycyclic aromatic component and a light hydrocarbon having 2 to 8 carbon atoms to BTX using a zeolite catalyst (Patent Literatures 7 and 8).

However, the methods (1) and (2) have a problem that the addition of high-pressure molecular hydrogen is necessary and the hydrogen consumption is also high. In addition, under hydrogenation conditions, LPG distillates and the like are largely produced as a by-product, requiring energy for separation and the like as well as lowering the efficiency of the raw material.

(3), the conversion of polycyclic aromatic components is not necessarily sufficient.

(4) is a combination of a BTX production technique using a light hydrocarbon as a raw material and a BTX production technique using a hydrocarbon containing a polycyclic aromatic component as a raw material, thereby improving the thermal balance. The BTX yield from the polycyclic aromatic component .

In addition, there is decomposed heavy oil (pyrolysis heavy oil) obtained from an ethylene production apparatus, which contains a polycyclic aromatic component at a high concentration similarly to LCO. This decomposed heavy oil is mostly used in a fuel such as a boiler in a combinatorium. As another utilization method of the decomposed heavy oil, it is known that an ethylene heavy end is treated in the presence of a solid acid catalyst in a hydrogen atmosphere to obtain a modified pitch obtained by removing an excess distillate to 500 캜 which is a raw material of the carbon fiber (Patent Document 9 , 10).

However, there is no known method for producing such BTX in high yield by feeding such pyrolysis heavy oil as a raw material.

Japanese Patent Application Laid-Open No. 61-283687 Japanese Patent Application Laid-Open No. 56-157488 Japanese Patent Application Laid-Open No. 61-148295 British Patent No. 1287722 Specification Japanese Patent Application Laid-Open No. 2007-154151 Japanese Patent Application Laid-Open No. 3-2128 Japanese Patent Laid-Open Publication No. 3-52993 Japanese Patent Application Laid-Open No. 3-26791 Japanese Patent Publication No. 4-30436 Japanese Patent Publication No. 4-30437

The present invention provides a method for efficiently producing BTX without containing molecular hydrogen from a raw material flow path containing hydrotreated oil of pyrolysis-resistant oil obtained from an ethylene production apparatus.

The inventors of the present invention have conducted diligent research in order to solve the above problems. As a result, it has been found that, while using a raw material oil containing hydrotreated oil of pyrolysis-resistant oil obtained from an ethylene production apparatus, The present inventors have found that BTX can be efficiently produced by contacting and reacting with a catalyst containing a non-silicate, and have completed the present invention.

That is, the process for producing an aromatic hydrocarbon (BTX)

A step of obtaining pyrolysis heavy oil from an ethylene production apparatus,

Hydrogenating the pyrolysis heavy oil to obtain hydrogenated oil;

And a decomposition reforming reaction step of bringing the feed oil containing the hydrotreated oil into contact with a catalyst for producing monocyclic aromatic hydrocarbons comprising crystalline aluminosilicate,

The raw oil having a distillation property end point of 400 DEG C or lower is used as the raw oil and the reaction pressure when the raw oil and the catalyst for the production of the monocyclic aromatic hydrocarbon are brought into contact with each other in the decomposition reforming step is 0.1 MPaG To 1.5 MPaG.

It is preferable that the hydrotreated oil has a content of two or more polycyclic aromatic hydrocarbons of 50 mass% or less and a content of one-ring aromatic hydrocarbons of 30 mass% or more.

The hydrotreated oil preferably has a content of hydrocarbons having an indane skeleton and an indene skeleton of 5 mass% or more.

The process of obtaining the oil hydrogenation, the step of distillation to remove the heavy oil and the thermal decomposition, distillation using the catalyst for hydrotreating a heavy oil by thermal cracking separated in the presence of hydrogen the hydrogen partial pressure of 0.7 to 20MPa, LHSV 0.05 to 2h ^-1, reaction And a hydrogenation treatment at a temperature of 200 캜 to 450 캜 and a hydrogen / oil ratio of 100 to 2000 NL / L.

Wherein the step of obtaining the hydrotreated oil comprises the steps of: subjecting the pyrolysed heavy oil to a hydrogen partial pressure of 0.7 to 20 MPa, a LHSV of 0.05 to 2 h ^-1 , a reaction temperature of 200 to 450 캜, a hydrogen / oil ratio of 100 To 2000 NL / L, and a step of distilling and separating the hydrogenated pyrolysis heavy oil.

Wherein the catalyst for hydrotreating comprises 10 to 30 mass% of at least one metal selected from Group 6 metals of the periodic table on the basis of the total catalyst mass, And 1 to 7% by mass of at least one metal selected from Group 10 metals.

At least one metal selected from Group 6 metals of the periodic table is molybdenum and / or tungsten, and at least one metal selected from Group 8 to Group 10 metals of the periodic table is cobalt and / or nickel desirable.

It is preferable that the catalyst for producing monocyclic aromatic hydrocarbons comprises gallium and / or zinc.

It is preferable that the catalyst for producing the monocyclic aromatic hydrocarbon includes phosphorus.

INDUSTRIAL APPLICABILITY According to the method for producing an aromatic hydrocarbon of the present invention, it is possible to efficiently produce BTX without the molecular hydrogen being present in the raw material flow path including the hydrotreated oil of the pyrolysis-resistant oil obtained from the ethylene production apparatus.

BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a view for explaining an embodiment of a process for producing aromatic hydrocarbons according to the present invention; FIG.

Hereinafter, a method for producing an aromatic hydrocarbon of the present invention will be described in detail with reference to the drawings. BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is an explanatory diagram of an embodiment of a method for producing an aromatic hydrocarbon of the present invention. FIG.

As shown in Fig. 1, the process for producing aromatic hydrocarbons according to the present embodiment is characterized in that a raw oil containing hydrotreated oil of pyrolytic crude oil obtained from an ethylene production apparatus is mixed with a catalyst for the production of monocyclic aromatic hydrocarbons containing crystalline aluminosilicate Contacting and reacting the crude oil with a catalyst for producing monocyclic aromatic hydrocarbons by using a material having an end point of distillation at 400 ° C or lower as the raw oil and carrying out contact between the raw oil and the catalyst for producing a monocyclic aromatic hydrocarbon under a pressure of 0.1 MPaG to 1.5 MPaG to be.

(Raw material oil)

The raw material oil relating to the production method of an aromatic hydrocarbon according to the present embodiment includes a hydrotreated oil of pyrolysis heavy oil obtained from an ethylene production apparatus and it is necessary that the end point of the distillation property is 400 DEG C or less. By setting the end point at 400 占 폚 or lower, the BTX yield can be increased in the decomposition reforming reaction step by contacting / reacting with a catalyst for producing monocyclic aromatic hydrocarbons, which will be described later. In order to further increase the BTX yield, the end point is preferably 350 DEG C or lower, more preferably 300 DEG C or lower. The lower limit value of the end point is preferably 200 占 폚 to 300 占 폚. The distillation property other than the end point is not particularly limited. However, in order to efficiently produce BTX, the 10 volume% effluent temperature (T10) is preferably 140 占 폚 to 220 占 폚, the 90% Or more and 380 ° C or less, more preferably T10 is 160 ° C or more and 200 ° C or less, and T90 is 240 ° C or more and 350 ° C or less.

Here, the distillation property is measured in accordance with the "petroleum product-distillation test method" specified in JIS K 2254.

Further, the raw material oil relating to the production method of aromatic hydrocarbons of the present embodiment may contain other base material as long as it includes hydrogenated oil of pyrolysis-resistant oil obtained from an ethylene production apparatus. Other substrates to be added to the hydrotreating oil will be described later.

(Pyrolysis heavy oil obtained from an ethylene production apparatus)

In the present embodiment, the pyrolysis intermediate oil (hereinafter also referred to as pyrolysis intermediate oil) obtained from the ethylene production apparatus refers to ethylene produced by pyrolysis of a raw material such as naphtha distillate, distillate and light oil distillate to produce chemicals such as ethylene, propylene and BTX Refers to residual oil obtained from the apparatus, and may be referred to as a heavy aromatic residual oil (HAR oil). The ethylene production apparatus includes a steam cracker (also referred to as a steam cracking apparatus). The raw material of the ethylene production apparatus is not particularly limited, but a naphtha distillate derived from petroleum is usually used in an amount of 80% or more. Examples of the naphtha distillate other than the naphtha distillate include diesel, cracked gasoline, cracked light oil, and desulfurized light oil.

Naphtha distillates and the like to pyrolyze a raw material to produce a chemical such as ethylene or propylene can be used under general conditions and is not particularly limited. For example, the raw material may be operated at a pyrolysis reaction temperature of 770 to 850 DEG C with a residence time (reaction time) of 0.1 to 0.5 seconds together with diluted water vapor. When the pyrolysis temperature is lower than 770 ° C, the pyrolysis reaction temperature is lower than 775 ° C, and more preferably 780 ° C or higher, because the pyrolysis does not progress and the desired product can not be obtained. On the other hand, if the pyrolysis temperature exceeds 850 deg. C, the gas production amount increases rapidly, which hinders the operation of the steam cracker. Therefore, the upper limit of the pyrolysis reaction temperature is more preferably 845 DEG C or lower, and further preferably 840 DEG C or lower. The steam / raw material (mass ratio) is preferably 0.2 to 0.9, more preferably 0.25 to 0.8, still more preferably 0.3 to 0.7. The retention time (reaction time) of the raw material is more preferably 0.15 to 0.45 second, and still more preferably 0.2 to 0.4 second.

(Properties of Pyrolysis Heavy Oil)

In the present embodiment, the properties of the pyrolysis heavy oil are not particularly defined, but it is preferable to have the following characteristics.

(T10) in the distillation test is 190 ° C or more and 230 ° C or less, 50% by volume or more and the outlet temperature (T50) is 210 ° or more and not more than 300 ° C, Hereinafter, the end point EP is preferably used in a range of 550 DEG C or higher and 650 DEG C or lower. If the end point is above 650 ° C, the content of the poisoning agent with respect to the catalyst such as heavy metals becomes large, and the lifetime of the catalyst is significantly lowered.

The dynamic viscosity of the pyrolysis heavy oil at 15 ° C is not less than 1.03 g / cm ^{3 and not} more than 1.08 g / cm ³ , the dynamic viscosity at 50 ° C is not less than 20 mm ² / s and not more than 45 mm ² / s, Is preferably not less than 200 mass ppm and not more than 700 mass ppm, the nitrogen content (nitrogen content) is not more than 20 mass ppm, and the aromatic content is not less than 80 vol%.

When the pyrolysis heavy oil is subjected to a hydrogenation treatment described later, the pyrolysis heavy oil may be subjected to hydrogenation treatment as it is. Further, as shown in Fig. 1, the pyrolysis heavy oil may be distilled and separated at a predetermined cut temperature (for example, boiling point 400.degree. C.) in the distillation column in advance, and then the hard component (hard distillation fraction) have.

Here, the distillation test means that it is measured in accordance with the "petroleum product-distillation test method" specified in JIS K 2254. The density at 15 캜 means that measured in accordance with the "Vibratory density test method" of "Density, mass and capacity conversion table (extract)" of JIS K 2249 "crude oil and petroleum products-density test method". The kinematic viscosity at 50 캜 means a value obtained in accordance with JIS K 2283 " Crude Oil and Petroleum Products-Kinetic Viscosity Test Method and Viscosity Index Calculation Method ". The sulfur content means the sulfur content measured in accordance with the " radiation excitation method " of " crude oil and petroleum product-sulfur test method " specified in JIS K 2541-1992. The nitrogen content means the nitrogen content measured in accordance with JIS K 2609 " crude oil and petroleum product-nitrogen content test method ". Aromatic fractions means the total aromatic content determined by the Petroleum Institute of Japan Act JPI-5S-49-97, "Petroleum Product-Hydrocarbon Type Test Method-High Performance Liquid Chromatograph".

(Hydrogenation treatment of pyrolysis heavy oil)

The pyrolysis heavy oil obtained from the ethylene production apparatus usually has a very large content of aromatic hydrocarbons. Therefore, in the process for producing aromatic hydrocarbons according to the present embodiment, the pyrolysis heavy oil is subjected to a hydrogenation treatment in the hydrotreating process, and the hydrogenation treatment of the required distillation fraction (or the necessary distillation fraction in the pyrolysis- I get oil. However, a large amount of hydrogen is required for hydrotreating the pyrolysis heavy oil until the hydrolysis is decomposed. Also, when the completely hydrogenated pyrolysis heavy oil is used in the feed oil, the yield of BTX is lowered, and a large amount of distillate- The production efficiency of BTX in the decomposition reforming reaction step by contacting and reacting with a catalyst for producing a monocyclic aromatic hydrocarbon, which will be described later, becomes very low.

In addition, the amount of heat generated in the hydrogenolysis reaction of the pyrolysis heavy oil is very large, so that the actual operation of the hydrogenation apparatus becomes difficult. In addition, since the boiling point range of the pyrolysis heavy oil is wide and the number of the three or more ring aromatic polycyclic aromatic hydrocarbons is large, the production efficiency of the BTX in the decomposition reforming step is very low.

As described above, it has been thought that it is difficult to efficiently produce BTX from pyrolysis heavy oil. However, the inventors of the present invention have conducted intensive studies and, as a result, have invented a new method for producing BTX from pyrolysis heavy oil very efficiently.

That is, in the present embodiment, the two-ring aromatic hydrocarbons in the pyrolysis heavy oil are selectively hydrogenated and converted into one-ring aromatic hydrocarbons (such as naphthenobenzenes) obtained by hydrogenating only one aromatic ring. Thereafter, the distillate converted into the monocyclic aromatic hydrocarbon is contacted with a catalyst containing crystalline aluminosilicate in the presence of low-pressure molecular hydrogen, and reacted to perform decomposition reforming reaction to produce BTX. Examples of the monocyclic aromatic hydrocarbon include indane, tetralin, and alkylbenzene.

According to this method, the amount of hydrogen required to obtain BTX from the pyrolysis heavy oil is minimized, so that the hydrogen consumption amount can be suppressed and the heat generation amount, which is a big problem, can be suppressed. For example, when naphthalene, which is a typical example of a bicyclic aromatic hydrocarbon, is hydrogenated with decalin, the hydrogen consumption per mole of naphthalene is 5 moles. When hydrogenating naphthalene with tetralin, the hydrogen consumption per mole of naphthalene is 2 moles. There is also a large amount of distillate containing indene in pyrolysis heavy oil, and the amount of hydrogen consumed to hydrogenate the distillate to the distillate stream is smaller than that required to hydrogenate naphthalene to tetralin. Therefore, according to the above method, it becomes possible to more efficiently convert the bicyclic aromatic hydrocarbons in the pyrolysis heavy oil into naphthenobenzenes.

Further, when the pyrolysis heavy oil is subjected to hydrotreating, a heavy amount consuming a large amount of hydrogen and adversely affecting the performance of the catalyst for producing a monocyclic aromatic hydrocarbon, which will be described later, is distilled and separated from the distillation tower as shown in Fig. 1, It is preferable to remove it from the flow path beforehand. For the distillation separation in the distillation column, for example, the boiling point of 400 ° C is used as the cut temperature, and the mixture is separated into a light component and a heavy component of pyrolysis heavy oil. By performing the separation treatment in this manner, it becomes possible to manufacture BTX more efficiently. The cut temperature at the time of distillation separation is preferably 300 ° C to 350 ° C, more preferably 210 ° C to 300 ° C.

The separation of the distillation by the distillation column may be carried out in the subsequent stage instead of the preceding stage of the hydrotreating process, as indicated by the broken line arrow in FIG. In this case as well, since the heavy component is separated from the pyrolysis heavy oil after the hydrotreating treatment and the hard component is flowed through the raw material, adverse effects due to the above-described heavy component can be prevented.

Thus, the distillate (hard matter) of the hydrotreated heavy crude oil can be efficiently converted into BTX by the contact reaction with the catalyst for producing monocyclic aromatic hydrocarbons according to the present embodiment. Further, since this hard component also generates hydrogen by the BTX production reaction, it is also possible to use this hydrogen for the hydrogenation treatment of the pyrolysis heavy oil again.

The hydrogenation treatment of the pyrolysis heavy oil can be carried out in a known hydrogenation reactor. In the hydrogenation treatment in this hydrogenation reactor, the hydrogen partial pressure at the inlet of the reactor is preferably 0.7 to 20 MPa. The lower limit is more preferably 1 MPa or higher, more preferably 1.5 MPa or higher, even more preferably 2 MPa or higher. The upper limit is more preferably 15 MPa or less, and further preferably 10 MPa or less. When the hydrogen partial pressure is less than 0.7 MPa, the generation of coke on the catalyst becomes severe and the catalyst life is shortened. On the other hand, when the hydrogen partial pressure exceeds 20 MPa, the construction cost of the reactor, peripheral equipment, and the like is increased, which may result in loss of economical efficiency.

The liquid hourly space velocity (LHSV) in the hydrogenation treatment of the pyrolysis heavy oil is preferably 0.05 to 2 h ^-1 . As the lower limit of 0.1h ^-1 or more it is more preferred, and a 0.2h ^-1 or more is more preferred. The upper limit as 1.9h ^-1 or less is more preferable, and 1.8h ^-1 or less is more preferable. When the LHSV is less than 0.05 h < ^-1 >, the construction cost of the reactor becomes excessive, which may result in loss of economic efficiency. On the other hand, when LHSV exceeds 2h ^-1, a hydrogen treatment of heavy oil pyrolysis not sufficiently achieved there is a fear that the reactivity of the decomposition reforming process worse.

The reaction temperature in the hydrogenation treatment of the pyrolysis heavy oil is preferably 200 to 450 ° C. The lower limit is more preferably 220 DEG C or higher, and still more preferably 250 DEG C or higher. The upper limit is more preferably 440 占 폚 or lower, and still more preferably 430 占 폚 or lower. When the reaction temperature is lower than 200 캜, the hydrogenation treatment of the pyrolysis heavy oil tends not to be sufficiently achieved. On the other hand, when the reaction temperature exceeds 450 ° C, generation of gas components as by-products is increased, and the yield of the hydrogenation treatment oil is lowered, which is not preferable.

The hydrogen / oil ratio in the hydrogenation treatment of the pyrolysis heavy oil is preferably 100 to 2000 NL / L. The lower limit is more preferably 110 NL / L or more, and more preferably 120 NL / L or more. The upper limit is more preferably 1800 N / L or less, and more preferably 1500 NL / L or less. When the hydrogen / oil ratio is less than 100 NL / L, the generation of coke on the catalyst at the reactor outlet proceeds and the catalyst life tends to be shortened. On the other hand, when the hydrogen / oil ratio exceeds 2000 NL / L, the construction cost of the recycle compressor becomes excessive, which may lead to loss of economical efficiency.

The type of reaction in the hydrogenation treatment of the pyrolysis heavy oil is not particularly limited, but usually, it can be selected from various processes such as a fixed phase and a mobile phase. Among them, a stationary phase is preferable.

Further, the reactor is preferably a tower.

The catalyst for hydrogenation used in the hydrogenation treatment of the pyrolysis heavy oil contains at least one metal selected from Group 6 metals of the periodic table and at least one metal selected from Group 8 to Group 10 metals of the periodic table . As the Group 6 metal of the periodic table, molybdenum, tungsten, and chromium are preferable, and molybdenum and tungsten are particularly preferable. As the Group 8 to Group 10 metals of the periodic table, iron, cobalt and nickel are preferable, and cobalt and nickel are more preferable. These metals may be used alone or in combination of two or more. Specific examples of the combination of metals include molybdenum-cobalt, molybdenum-nickel, tungsten-nickel, molybdenum-cobalt-nickel, and tungsten-cobalt-nickel. Here, the periodic table refers to the long period periodic table defined by the International Union of Pure and Applied Chemistry (IUPAC).

It is preferable that the metal for the hydrotreating treatment be carried on an inorganic carrier containing aluminum oxide. Preferable examples of the inorganic carrier containing aluminum oxide include alumina, alumina-silica, alumina-boria, alumina-titania, alumina-zirconia, alumina-magnesia, alumina-silica-zirconia, alumina- And various clay minerals such as montmorillonite, and the like, and alumina is particularly preferable.

Wherein the catalyst for hydrotreating comprises at least one metal selected from Group 6 metals of the periodic table based on the total mass of the catalyst, which is the total mass of the inorganic carrier and the metal, to an inorganic carrier containing aluminum oxide And 1 to 7% by mass of at least one metal selected from Group 8 to Group 10 metals of the Periodic Table. When the loading amount of the Group 6 metal of the periodic table or the loading amount of the Group 8 to Group 10 metals in the periodic table is less than the respective lower limits, the catalyst tends not to exhibit sufficient hydrotreatment activity, while exceeding the respective upper limits , There is a tendency that the catalytic cost is increased and cohesion of the supported metal tends to occur and the catalyst does not exhibit sufficient hydrogenation treatment activity.

The precursor of the metal species to be used when the metal is supported on the inorganic support is not limited, but an inorganic salt or an organic metal compound of the metal is used, and a water-soluble inorganic salt is preferably used. In the carrying process, it is preferable to carry out carrying using a solution of these metal precursors, preferably an aqueous solution. As the supporting operation, known methods such as a dipping method, an impregnation method and coprecipitation method are preferably adopted.

The carrier on which the metal precursor is supported is preferably calcined in the presence of oxygen after drying, so that the metal species is once an oxide. Further, it is preferable that the metal species is a sulfide by sulphiding treatment, which is called preliminary sulphurization, before the hydrogenation treatment of the pyrolysis heavy oil.

The condition of the preliminary sulfuration is not particularly limited, but a sulfur compound is added to a distillate oil distillate or a pyrolysis intermediate oil (hereinafter referred to as a preliminary sulfidization raw oil) and the LHSV is 1 to 2 h ^-1 , Is preferably brought into contact with the hydrogenation treatment catalyst continuously under the same conditions as those in the hydrotreating operation under the conditions of a treatment time of 48 hours or more. The sulfur compound to be added to the preliminary sulfiding raw material oil is not limited, but dimethyl disulfide (DMDS), sulfazole, hydrogen sulfide and the like are preferable, and they are added to the preliminary sulfiding raw oil in an amount of about 1 mass% desirable.

(Hydrogenation treatment of pyrolysis heavy oil)

It is preferable that the hydrotreated oil of the pyrolysis heavy oil relating to the production method of the aromatic hydrocarbon of the present embodiment obtained in the hydrogenation treatment described above has the following characteristics.

The distillative phase preferably has a 10% by volume outflow temperature (T10) of 140 to 200 DEG C and a 90% by volume outflow temperature (T90) of 200 to 380 DEG C, more preferably T10 of 160 to 190 DEG C, 210 deg. C or higher and 350 deg. C or lower. When T10 is less than 140 占 폚, there is a possibility that xylene which is one of the target products is contained in the raw material oil including the hydrogenated oil, which is not preferable. On the other hand, when T90 exceeds 380 DEG C (when the catalyst becomes heavier), the catalytic performance decreases due to metal poisoning of the hydrotreating catalyst, coke precipitation, etc., and coke precipitation on the catalyst for producing monocyclic aromatic hydrocarbons increases, It is not preferable from the point of view that the amount of hydrogen consumed increases and it becomes uneconomical.

In most cases, in order to hydrotreate pyrolysis heavy oil relating to the production of aromatic hydrocarbons of the present embodiment, it is necessary to carry out distillation separation using a distillation column or the like as described above. After distillation and separation of pyrolysis heavy oil as described above, Alternatively, the pyrolysis heavy oil may be hydrotreated in a hydrotreating step and then separated by distillation. From the viewpoint of efficient use of hydrogen, it is preferable to carry out the hydrogenation treatment after distillation and separation of the pyrolysis heavy oil.

The degree of hydrogenation of pyrolysis heavy oil is not particularly limited as long as the hydrogenation of the polycyclic aromatic hydrocarbon in the pyrolysis heavy oil proceeds, but from the viewpoint of the production reaction of BTX described later, the hydrotreated pyrolysis The heavy oil, that is, the hydrotreating oil preferably has the following characteristics.

As the hydrotreating oil (hydrotreated oil of the pyrolysis-resistant oil contained in the raw material oil), the content of the one-ring aromatic hydrocarbon contained therein is preferably 30 mass% or more, more preferably 50 mass% or more. The term "monocyclic aromatic hydrocarbon" as used herein means a hydrocarbon having one aromatic ring such as alkylbenzene or naphthenobenzene. When the content of the one-ring aromatic hydrocarbon is less than 30% by mass, BTX can not be efficiently produced, which is not preferable.

The content of the two or more polycyclic aromatic hydrocarbons contained in the hydrotreatment flow path is preferably 50 mass% or less, more preferably 30 mass% or less, and further preferably 20 mass% or less. Among polycyclic aromatic hydrocarbons, the content of polycyclic aromatic hydrocarbons having three or more rings is preferably 20 mass% or less, more preferably 10 mass% or less, still more preferably 5 mass% or less. When the content of the polycyclic aromatic hydrocarbon having two or more rings is more than 50% by mass, it is not preferable because BTX can not be efficiently produced.

The content of the naphthenic hydrocarbon contained in the hydrotreating process is not particularly limited, but is preferably 50% by mass or less, and more preferably 30% by mass or less. When the content of the naphthene hydrocarbon is more than 50% by mass, the amount of hydrogen consumed in the hydrotreating process of the pyrolysis heavy oil becomes excessively large, which is not economical, and the amount of gas generated in the BTX production process (decomposition reforming reaction process) And the efficiency is lowered.

Further, in this hydrotreating process, the content of hydrocarbons having an indane skeleton and an indene skeleton contained therein is preferably 5 mass% or more, more preferably 10 mass% or more, and still more preferably 20 mass% or more. The upper limit of the content of hydrocarbons having an indane skeleton and an indene skeleton is not particularly limited, but is preferably 90 mass% or less. Since pyrolysis heavy oil is a by-product mainly derived from pyrolysis reaction such as naphtha, unlike petroleum distillate (LCO, etc.) obtained from catalytic cracking and the like, it has a feature of containing a large amount of hydrocarbons having an indene skeleton. Even if hydrocarbons having this indene skeleton are hydrogenated and become hydrocarbons having an indane skeleton, they become a good raw material in the production of BTX, and the amount of hydrogen consumed is smaller than that of the tetralin from naphthalene. (5% by mass or more) is preferable.

Examples of hydrocarbons having an indane skeleton include indane, methylindane, ethylindane, dimethylindane, diethylindane, and the like. In the present embodiment, it is particularly preferable that an indane or methylindane is contained. Examples of hydrocarbons having an indene skeleton include indene, methylindene, ethylindene, dimethylindene, diethylindene, and the like. In the present embodiment, it is particularly preferable to contain indene and methylindene.

The content of the monocyclic aromatic hydrocarbon, the content of the polycyclic aromatic hydrocarbon, the content of the naphthenic hydrocarbon, and the content of hydrocarbons having the indane skeleton and the indene skeleton refer to the content measured by FID gas chromatograph analysis.

(Base material which can be used by mixing with hydrotreated oil of pyrolysis heavy oil)

(LCO, heavy cycle oil (HCO), cracked residual oil (CLO), and the like) generated in the FCC apparatus, if necessary, as a raw material oil in the present embodiment essentially comprises hydrogenated oil of the above- , Partial distillation (partially hydrogenated LCO, partially hydrogenated HCO, partially hydrogenated CLO, etc.) produced from partially hydrogenated effluent produced in the FCC apparatus, effluent produced in the coker, distillation product obtained by partially hydrogenating the effluent produced in the coker , Hydrocracked distillate containing a large amount of naphthene fraction, distillate distillate produced in heavy oil hydrocracking apparatus or heavy oil hydrodesulfurization apparatus, distillate obtained by hydrogenating distillate obtained from oil sand, or the like, It may be mixed with the hydrotreating oil to make the raw material flow path.

However, even when raw materials other than the hydrotreated oil are mixed to form the raw oil, the raw material oil to be obtained is produced so that the end point of the distillation property is 400 ° C or less as described above.

In this manner, in the present embodiment, the raw oil is transferred to the decomposition reforming reaction step as shown in Fig. 1, and the raw material oil containing the hydrotreated oil of the pyrolysis- BTX is prepared by contacting with a catalyst.

(Catalyst for Monocyclic Aromatic Hydrocarbon Production)

The catalyst for producing monocyclic aromatic hydrocarbons contains crystalline aluminosilicate.

[Crystalline aluminosilicate]

Since the crystalline aluminosilicate can increase the yield of BTX, it is preferably a pore-zeolite and / or a large-pore zeolite.

The mesoporous zeolite is a zeolite having a 10-membered skeleton structure. Examples of the mesoporous zeolite include AEL, EUO, FER, HEU, MEL, MFI, NES, TON and WEI Zeolite. Of these, the MFI type is preferable because the yield of BTX can be further increased.

The major pore zeolite is a zeolite having a 12-membered skeleton structure, and examples of the major pore zeolite include AFI type, ATO type, BEA type, CON type, FAU type, GME type, LTL type, MOR type, MTW type, And a zeolite having a crystal structure. Of these, the BEA type, the FAU type and the MOR type are preferable in view of industrial availability, and the BEA type is more preferable because the BTX yield can be increased.

Crystalline aluminosilicates may contain, in addition to the pore-pore zeolite and the large pore zeolite, a micro-pore zeolite having a skeleton structure having a 10-membered ring structure or less, and an ultrafine zeolite having a skeletal structure having 14 or more membered rings.

Examples of the microporous zeolite include zeolites of ANA type, CHA type, ERI type, GIS type, KFI type, LTA type, NAT type, PAU type and YUG type crystal structure.

Examples of the ultra-fine pore zeolite include zeolite having a CLO type or VPI type crystal structure.

In the case where the decomposition reforming reaction process is a fixed phase reaction, the content of crystalline aluminosilicate in the catalyst for producing monocyclic aromatic hydrocarbons is preferably 60 to 100% by mass based on 100% by mass of the entire catalyst for producing monocyclic aromatic hydrocarbons, , More preferably 70 to 100 mass%, and particularly preferably 90 to 100 mass%. When the content of the crystalline aluminosilicate is 60 mass% or more, the yield of BTX can be sufficiently increased.

When the decomposition reforming reaction step is a reaction of the fluidized phase, the content of the crystalline aluminosilicate in the catalyst for producing monocyclic aromatic hydrocarbons is preferably 20 to 60% by mass based on 100% by mass of the whole catalyst for producing monocyclic aromatic hydrocarbons, , More preferably 30 to 60 mass%, and particularly preferably 35 to 60 mass%. When the content of the crystalline aluminosilicate is 20 mass% or more, the yield of BTX can be sufficiently increased. If the content of the crystalline aluminosilicate exceeds 60% by mass, the content of the binder that can be incorporated in the catalyst becomes small, and the resulting product may not be suitable for use in the fluidized bed.

[Phosphorus, boron]

In the catalyst for producing monocyclic aromatic hydrocarbons, it is preferable to contain phosphorus and / or boron. When the catalyst for producing monocyclic aromatic hydrocarbons contains phosphorus and / or boron, the BTX yield can be prevented from decreasing with time and coke formation on the surface of the catalyst can be suppressed.

Examples of the method for containing phosphorus in the catalyst for producing monocyclic aromatic hydrocarbons include ion exchange, impregnation, and the like. Specifically, there is a method of supporting phosphorus in crystalline aluminosilicate or crystalline alumino silicate silicate or crystalline alumino phosphoric silicate, a method of containing a phosphorus compound in the synthesis of zeolite to cause a part of the crystalline aluminosilicate A method of using a crystal accelerator containing phosphorus in the synthesis of zeolite, and the like. The aqueous phosphate-containing aqueous solution to be used at that time is not particularly limited, and those prepared by dissolving phosphoric acid, ammonium dihydrogenphosphate, ammonium dihydrogenphosphate and other water-soluble phosphate in water at an arbitrary concentration can be preferably used.

Examples of the method for containing boron in the catalyst for producing monocyclic aromatic hydrocarbons include ion exchange, impregnation, and the like. Specifically, a method of supporting boron on a crystalline aluminosilicate or a crystalline aluminogalc silicate or a crystalline alumino sapphirelite, a method of containing a boron compound in the synthesis of zeolite to convert a part of the crystalline aluminosilicate to a boron , A method of using a crystal accelerator containing boron in the synthesis of zeolite, and the like.

The content of phosphorus and / or boron in the catalyst for producing monocyclic aromatic hydrocarbons is preferably 0.1 to 10 mass%, more preferably 0.5 mass% or more, and upper limit is 9 mass% or less By mass, and particularly preferably 8% by mass or less. The content of phosphorus and / or boron relative to the total weight of the catalyst is 0.1% by mass or more, so that the yield of BTX over time can be prevented from decreasing, and the yield of BTX can be increased by 10% by mass or less.

[Gallium, zinc]

The catalyst for producing monocyclic aromatic hydrocarbons may contain gallium and / or zinc if necessary. When gallium and / or zinc is contained, the production ratio of BTX can be increased.

Examples of the form of containing gallium in the catalyst for producing monocyclic aromatic hydrocarbons include those in which gallium is inserted (crystalline aluminogalosilicate) in the lattice framework of crystalline aluminosilicate, gallium supported on crystalline aluminosilicate Crystalline aluminosilicate), and those containing both of them.

Examples of the form of zinc contained in the catalyst for producing monocyclic aromatic hydrocarbons include those in which zinc is inserted in the lattice framework of crystalline aluminosilicate (crystalline alumino-soft silicate), those in which zinc is supported on crystalline aluminosilicate Crystalline aluminosilicate), and those containing both of them.

Crystalline aluminogalosilicate and crystalline aluminoacylate have a structure in which SiO ₄ , AlO ₄ and GaO ₄ / ZnO ₄ structures are present in the framework. Further, crystalline aluminogalosilicate and crystalline aluminoacylate silicate can be obtained, for example, by gel crystallization by hydrothermal synthesis, or by a method of inserting gallium or zinc into the lattice framework of crystalline aluminosilicate. In addition, crystalline aluminogalosilicates, crystalline aluminoacanate silicates are obtained by a method of inserting aluminum into the lattice framework of crystalline gallosilicate or crystalline zinc silicate.

The gallium-supported crystalline aluminosilicate is obtained by carrying gallium to a crystalline aluminosilicate by a known method such as an ion exchange method or an impregnation method. The gallium source used at this time is not particularly limited, and examples thereof include gallium salts such as gallium nitrate and gallium chloride, and gallium oxide.

The zinc-supported crystalline aluminosilicate is obtained by supporting zinc on the crystalline aluminosilicate by a known method such as an ion exchange method or an impregnation method. The zinc source to be used at this time is not particularly limited, and examples thereof include zinc salts such as zinc nitrate and zinc chloride, and zinc oxide.

In the case where the catalyst for producing monocyclic aromatic hydrocarbons contains gallium and / or zinc, the content of gallium and / or zinc in the catalyst for producing monocyclic aromatic hydrocarbons is preferably 0.01 to 5.0% by mass based on 100% by mass of the whole catalyst , And more preferably 0.05 to 2.0 mass%. When the content of gallium and zinc is 0.01 mass% or more, the production ratio of BTX can be increased, and when it is 5.0 mass% or less, the yield of BTX can be increased.

[shape]

The catalyst for the production of monocyclic aromatic hydrocarbons may be in the form of powder, granule, pellet or the like depending on the reaction type. For example, in the case of a fluid phase, it is in the form of powder, and in the case of a stationary phase, it is in the form of granular or pellet. The average particle size of the catalyst used in the fluidized bed is preferably 30 to 180 占 퐉, more preferably 50 to 100 占 퐉. The bulk density of the catalyst used in the fluidized bed is preferably 0.4 to 1.8 g / cc, more preferably 0.5 to 1.0 g / cc.

The average particle diameter represents a particle diameter of 50% by mass in the particle size distribution obtained by classifying by sieve, and the bulk density is a value measured by the method of JIS standard R9301-2-3.

In the case of obtaining a granular or pellet-shaped catalyst, an oxide which is inactive to the catalyst may be mixed as a binder, if necessary, and then molded using various molding machines.

When the catalyst for producing monocyclic aromatic hydrocarbons contains an inorganic oxide such as a binder, phosphorus may be used as the binder.

(Reaction type)

In the present embodiment, the reaction form when the raw oil is brought into contact with and reacted with the monocyclic aromatic hydrocarbon catalyst includes a fixed phase, a mobile phase, and a fluidized phase. In the present embodiment, since the heavy oil (hydrotreated oil of pyrolytic cracked oil) is used as a raw material, a fluidized bed capable of continuously removing coke attached to the catalyst and capable of performing stable reaction is preferable, A continuous regeneration fluidized bed in which the catalyst can be circulated and the reaction-regeneration can be repeated continuously is particularly preferable. It is preferable that the raw oil when contacting with the catalyst is in a gaseous state. In addition, the raw oil may be diluted with a gas if necessary. When unreacted raw material oil is generated, it may be recycled if necessary.

(Reaction temperature)

The reaction temperature at the time of contacting and reacting the raw oil with the catalyst is not particularly limited, but is preferably from 350 to 700 ° C, more preferably from 450 to 650 ° C. When the reaction temperature is less than 350 ° C, the reaction activity is not sufficient. When the reaction temperature exceeds 700 ° C, the catalyst becomes energetically unfavorable and catalyst regeneration becomes difficult.

(Reaction pressure)

The reaction pressure when the raw oil is contacted and reacted with the catalyst is 0.1 MPaG to 1.5 MPaG. That is, contact between the raw oil and the catalyst for producing monocyclic aromatic hydrocarbons according to the present embodiment is carried out at a pressure of 0.1 MPaG to 1.5 MPaG.

In the present embodiment, since the reaction pattern is completely different from that of the conventional method by hydrocracking, no high pressure condition that is dominant in hydrocracking is required. On the contrary, a high pressure higher than necessary promotes decomposition and is not preferable because it causes by-product a non-intended light gas. In addition, it is advantageous in terms of the design of the reaction apparatus that the high pressure condition is not required. On the other hand, in the present embodiment, the use of an active hydrogen transfer reaction is emphasized, and in this respect, it has been found that the pressurizing conditions are superior to those under normal pressure or reduced pressure. That is, when the reaction pressure is 0.1 MPaG to 1.5 MPaG, it is possible to efficiently perform the hydrogen transfer reaction.

(Contact time)

The contact time of the raw oil and the catalyst for producing a monocyclic aromatic hydrocarbon is not particularly limited as long as a desired reaction proceeds. For example, the gas passage time on the catalyst for producing a monocyclic aromatic hydrocarbon is preferably 1 to 300 seconds, and the lower limit is 5 seconds Or more, and the upper limit is more preferably 150 seconds or less. When the contact time is 1 second or more, the reaction can be reliably performed. When the contact time is 300 seconds or less, the accumulation of carbonaceous material in the catalyst by caulking or the like can be suppressed. Or the amount of light gas generated due to decomposition can be suppressed.

<Examples>

Hereinafter, the present invention will be described more specifically based on examples and comparative examples, but the present invention is not limited to these examples.

[Manufacturing method of hydrogenated oil of pyrolysis heavy oil]

(Production of catalyst for hydrogenation treatment)

Water glass No. 3 was added to 1 kg of a sodium aluminate aqueous solution having a concentration of 5 mass%, and the mixture was placed in a container kept at 70 캜. A solution prepared by adding an aqueous titanium sulfate (IV) solution (24 mass% as TiO ₂ content) to 1 kg of an aqueous solution of aluminum sulfate having a concentration of 2.5 mass% was prepared in a separate vessel kept at 70 캜, Was added dropwise to an aqueous solution containing sodium aluminate for 15 minutes. The amount of the water glass and the aqueous solution of titanium sulfate was adjusted so as to have a predetermined content of silica and titania.

The time point when the pH of the mixed solution reached 6.9 to 7.5 was regarded as an end point, and the resulting slurry product was passed through a filter and taken out by filtration to obtain a cake-like slurry. This cake-like slurry was transferred to a container equipped with a reflux condenser, 300 ml of distilled water and 3 g of a 27% aqueous ammonia solution were added, and the mixture was heated and stirred at 70 ° C for 24 hours. The slurry after the stirring treatment was placed in a kneading apparatus and heated at 80 DEG C or higher to remove water and kneaded to obtain a kneaded product of the clay-like material.

The obtained kneaded product was extruded in the form of a cylinder having a diameter of 1.5 mm by an extruder, dried at 110 DEG C for 1 hour, and then calcined at 550 DEG C to obtain a molded carrier. 300 g of the molded support thus obtained was impregnated with 150 ml of distilled water by adding molybdenum trioxide, cobalt (II) hexahydrate hexahydrate, phosphoric acid (concentration 85%) and adding malic acid to dissolve it while spraying.

The amounts of molybdenum trioxide, cobalt (II) nitrate hexahydrate, and phosphoric acid used were adjusted to a predetermined loading amount. The sample impregnated with the impregnation solution was dried at 110 ° C for 1 hour and then calcined at 550 ° C to obtain catalyst A. Catalyst A contained 1.9% by mass of SiO ₂ , 2.0% by mass of TiO ₂ , 22.9% by mass of MoO ₃ , 2.5% by mass of CoO, and P ₂ O ₅ 4.0% by mass.

(Distillation separation of pyrolysis heavy oil)

Pyrolysis heavy crude oil A obtained from the ethylene production apparatus shown in Table 1 was separated by hard distillation to produce hard-pyrolysis heavy oil B and hard-pyrolyse heavy oil C shown in Table 2. The boiling range of the produced hard-pyrolysis heavy oil B and hard-pyrolysis heavy oil C is shown in Table 2. [

(Hydrogenation treatment of pyrolysis heavy oil)

The catalyst A was charged into a fixed-bed continuous-flow-type reaction apparatus, and the preliminary sulfuration of the catalyst was performed first. That is, the density was 851.6 kg / m ³ at 15 ° C, the initial distillation point 231 ° C in the distillation test, the final distillation point 376 ° C, 1.18 mass% of sulfur as sulfur atoms based on the mass of the pre- 1% by mass of DMDS was added to the distillate (pre-sulfiding raw oil) corresponding to the direct current system light oil on the basis of the mass of the distillate, and this DMDS was continuously supplied to the catalyst A for 48 hours.

Thereafter, using the hard-pyrolysis heavy oil B and the hard-pyrolysis heavy oil C shown in Table 2 as raw materials, the reaction temperature was 350 ° C, LHSV = 0.5h ^-1 , hydrogen ratio 750NL / L, The hydrogenation treatment was carried out. The characteristics of the hydrogenated oils B-1, B-2, C-1, C-2 and C-3 of the obtained pyrolysis heavy oils are shown in Table 3, respectively.

The distillation properties of Tables 1, 2 and 3 were measured in accordance with "Petroleum Products-Distillation Test Method" prescribed in JIS K 2254, respectively. The density (@ 15 DEG C) of Table 1 was measured in accordance with the &quot; petroleum product-distillation test method &quot; specified in JIS K 2254. The kinematic viscosity (50 캜) was measured in accordance with JIS K 2283, "Crude Oil and Petroleum Products-Kinematic Viscosity Test Method and Viscosity Index Calculation Method". The sulfur content was measured in accordance with the "crude oil and petroleum product-sulfur test method" prescribed in JIS K 2541.

For each of the compositions shown in Tables 1, 2, and 3, mass spectrometry (EMS ionization method: JMS-700, manufactured by Nippon Denshi Co., Ltd.) was performed on the saturated and aromatic components obtained by silica gel chromatography , According to ASTM D2425 "Standard Test Method for Hydrocarbon Types in Middle Distillates by Mass Spectrometry ". The contents of hydrocarbons having an indane skeleton and an indene skeleton were calculated by FID gas chromatographic analysis.

[Process for producing aromatic hydrocarbons]

[Catalyst Preparation Example 1 for Production of Monocyclic Aromatic Hydrocarbon]

Preparation of Catalyst Containing Ga and In-Supported Crystalline Aluminosilicate:

A solution containing 1706.1 g of sodium silicate (Sodium silicate 3, SiO ₂ : 28 to 30% by mass, Na: 9 to 10% by mass, residual water, manufactured by Nippon Kayaku Kogyo K.K.) and 2227.5 g of water (a) and, Al ₂ (SO _{4) 3} and 14 to 18H ₂ O (reagent grade, produced by Wako Pure Chemical Industries Kogyo (Co., Ltd.)): 64.2g, tetrapropylammonium _{bromide: 369.2g, H 2 SO 4 (} 97 parts by mass %): 152.1 g, NaCl: 326.6 g, and water: 2975.7 g.

Subsequently, while the solution (A) was stirred at room temperature, the solution (B) was slowly added to the solution (A).

The resulting mixture was stirred vigorously for 15 minutes in a mixer, and the gel was broken to obtain a homogeneous finely divided state.

Subsequently, this mixture was placed in an autoclave made of stainless steel and subjected to a crystallization operation under a magnetic pressure at a temperature of 165 DEG C for 72 hours and a stirring speed of 100 rpm. After the crystallization operation was completed, the product was filtered to recover the solid product, and washed and filtered five times using about 5 liters of deionized water. The solid obtained by filtration was dried at 120 캜 and further calcined at 550 캜 for 3 hours under the flow of air.

As a result of X-ray diffraction analysis (model name: Rigaku RINT-2500V), it was confirmed that the obtained fired product had an MFI structure. The SiO ₂ / Al ₂ O ₃ ratio (molar ratio) by the fluorescent X-ray analysis (model name: Rigaku ZSX101e) was 64.8. The aluminum element contained in the lattice framework calculated from this result was 1.32 mass%.

Subsequently, a 30 mass% ammonium nitrate aqueous solution was added at a rate of 5 ml per 1 g of the obtained baked product, and the mixture was heated and stirred at 100 캜 for 2 hours, followed by filtration and washing with water. This operation was repeated four times and then dried at 120 DEG C for 3 hours to obtain an ammonium type crystalline aluminosilicate.

Thereafter, calcination was carried out at 780 DEG C for 3 hours to obtain a proton-type crystalline aluminosilicate.

Subsequently, 120 g of the gallium nitride aqueous solution was impregnated with 120 g of the obtained proton-type crystalline aluminosilicate so that gallium of 0.4 mass% (a total mass of crystalline aluminosilicate of 100 mass%) was carried, and dried at 120 deg. Thereafter, the mixture was calcined at 780 占 폚 for 3 hours under the flow of air to obtain gallium-supported crystalline aluminosilicate.

30 g of the ammonium dihydrogen phosphate aqueous solution was impregnated with 30 g of the obtained gallium-containing crystalline aluminosilicate so that 0.7 mass% of phosphorus (the total mass of crystalline aluminosilicate was 100 mass%) was impregnated and dried at 120 ° C. Thereafter, the mixture was calcined at 780 DEG C for 3 hours under the flow of air to obtain a catalyst containing crystalline aluminosilicate and gallium and phosphorus. In order to exclude the effect of the obtained catalyst on the initial activity, hydrothermal treatment was carried out at an operating temperature of 650 ° C, a treatment time of 6 hours, and an atmosphere of steam of 100 mass%. Thereafter, the hydrothermal treated catalyst thus obtained was subjected to tablet shaping by applying a pressure of 39.2 MPa (400 kgf), pulverized and adjusted to a size of 20 to 28 mesh to obtain a granular catalyst B.

[Catalyst Preparation Example 2 for Production of Monocyclic Aromatic Hydrocarbon]

Preparation of a catalyst comprising Zn and phosphorus-supported crystalline aluminosilicate:

A solution containing 1706.1 g of sodium silicate (Sodium silicate 3, SiO ₂ : 28 to 30% by mass, Na: 9 to 10% by mass, residual water, manufactured by Nippon Kayaku Kogyo K.K.) and 2227.5 g of water (a) and, Al ₂ (SO _{4) 3} and 14 to 18H ₂ O (reagent grade, produced by Wako Pure Chemical Industries Kogyo (Co., Ltd.)): 64.2g, tetrapropylammonium _{bromide: 369.2g, H 2 SO 4 (} 97 parts by mass %): 152.1 g, NaCl: 326.6 g, and water: 2975.7 g.

Subsequently, while the solution (A) was stirred at room temperature, the solution (B) was slowly added to the solution (A).

The resulting mixture was stirred vigorously for 15 minutes in a mixer, and the gel was broken to obtain a homogeneous finely divided state.

Subsequently, this mixture was placed in an autoclave made of stainless steel and subjected to a crystallization operation under a magnetic pressure at a temperature of 165 DEG C for 72 hours and a stirring speed of 100 rpm. After the crystallization operation was completed, the product was filtered to recover the solid product, and washed and filtered five times using about 5 liters of deionized water. The solid obtained by filtration was dried at 120 캜 and further calcined at 550 캜 for 3 hours under the flow of air.

As a result of X-ray diffraction analysis (Rigaku RINT-2500V), it was confirmed that the obtained fired product had an MFI structure. The SiO ₂ / Al ₂ O ₃ ratio (molar ratio) by the fluorescent X-ray analysis (model name: Rigaku ZSX101e) was 64.8. The aluminum element contained in the lattice framework calculated from this result was 1.32 mass%.

Subsequently, a 30 mass% ammonium nitrate aqueous solution was added at a rate of 5 ml per 1 g of the obtained baked product, and the mixture was heated and stirred at 100 캜 for 2 hours, followed by filtration and washing with water. This operation was repeated four times and then dried at 120 DEG C for 3 hours to obtain an ammonium type crystalline aluminosilicate.

Thereafter, calcination was carried out at 780 DEG C for 3 hours to obtain a proton-type crystalline aluminosilicate.

Subsequently, 120 g of an aqueous solution of zinc nitrate was impregnated with 120 g of the obtained proton-type crystalline aluminosilicate so that zinc of 0.4 mass% (a total mass of crystalline aluminosilicate of 100 mass%) was carried, and dried at 120 deg. Thereafter, the mixture was calcined at 780 캜 for 3 hours under the flow of air to obtain a catalyst containing zinc-supported crystalline aluminosilicate.

Subsequently, 30 g of the obtained zinc-supported crystalline aluminosilicate was impregnated with 30 g of an aqueous solution of ammonium hydrogenphosphate so that 0.7 mass% of phosphorus (the total mass of crystalline aluminosilicate was 100 mass%) was impregnated and dried at 120 ° C. Thereafter, the mixture was calcined at 780 ° C for 3 hours under the flow of air to obtain a catalyst containing crystalline aluminosilicate and zinc and phosphorus. In order to exclude the effect of the obtained catalyst on the initial activity, hydrothermal treatment was carried out at an operating temperature of 650 ° C, a treatment time of 6 hours, and an atmosphere of steam of 100 mass%. Thereafter, the hydrothermal treated catalyst thus obtained was subjected to tablet shaping by applying a pressure of 39.2 MPa (400 kgf), pulverized and adjusted to a size of 20 to 28 mesh to obtain a granular catalyst C.

[Examples 1 to 6 and Comparative Examples 1 to 3]

(Production of aromatic hydrocarbons)

Under the conditions of a reaction temperature of 550 DEG C, a reaction pressure of 0.3 MPaG and a molecular hydrogen coexistence, the raw materials shown in Table 4 were fed to the corresponding catalysts . As shown in Table 4, Examples 1 to 6 and Comparative Examples 1 to 3 were formed by the combination of the raw material oil and the catalyst used. Nitrogen was introduced as a diluent so that the contact time of the raw oil and the catalyst was 10 seconds when each raw oil was contacted and reacted with the catalyst.

The reaction was conducted under the above conditions for 30 minutes to prepare BTX, and the composition of the product was analyzed by FID gas chromatograph directly connected to the reaction apparatus to evaluate the catalytic activity at the initial stage of the reaction. The evaluation results are shown in Table 4.

From the results shown in Table 4, Examples 1 to 6 using hydrotreated oil of pyrolytic crude oil having a predetermined property as raw material flow channels were compared with those of Comparative Examples 1 to 3 using pyrolytic crude oil not subjected to hydrogenation treatment as BTX It was found that the product can be produced with good yield.

Therefore, in Examples 1 to 6, it was confirmed that BTX can be efficiently produced without the molecular hydrogen being present in the raw material flow path including the hydrotreated oil of pyrolysis-resistant oil obtained from the ethylene production apparatus.

Although the preferred embodiments of the present invention have been described above, the present invention is not limited to these embodiments. Additions, omissions, substitutions, and other modifications can be made without departing from the spirit of the present invention. The present invention is not limited by the foregoing description, but is only limited by the appended claims.

&Lt; Industrial applicability >

INDUSTRIAL APPLICABILITY According to the method for producing aromatic hydrocarbons of the present invention, it is possible to efficiently produce BTX from a raw material flow path containing hydrotreated oil of pyrolytic crude oil obtained from an ethylene production apparatus.

Claims (9)

A process for the production of aromatic hydrocarbons,
A step of obtaining pyrolysis heavy oil from an ethylene production apparatus,
Wherein the two-ring aromatic hydrocarbon in the pyrolysis heavy oil is selectively hydrogenated and converted into a one-ring aromatic hydrocarbon to obtain a hydrogenated oil having a content of two or more polycyclic aromatic hydrocarbons of 50 mass% or less and a content of the one-ring aromatic hydrocarbon of 30 mass% And
And a decomposition reforming reaction step of bringing the feed oil containing the hydrotreated oil into contact with a catalyst for producing monocyclic aromatic hydrocarbons comprising crystalline aluminosilicate,
A raw material oil having an end point of a distillation property of 400 DEG C or lower is used as the raw material oil,
Wherein the reaction pressure when the raw oil and the catalyst for the production of the monocyclic aromatic hydrocarbon are brought into contact in the decomposition reforming reaction step is from 0.1 MPaG to 1.5 MPaG. delete The process for producing an aromatic hydrocarbon according to claim 1, wherein the hydrotreated oil has a content of hydrocarbons having an indane skeleton and an indene skeleton of 5 mass% or more. The method according to claim 1, wherein the step of obtaining the hydrogenated oil comprises:
Distilling and separating the pyrolysis heavy oil,
Distillation separation is carried out in the presence of hydrogen at a hydrogen partial pressure of 0.7 to 20 MPa, an LHSV of 0.05 to 2 h ^-1 , a reaction temperature of 200 to 450 ° C. and a hydrogen / oil ratio of 100 to 2000 NL / L And a step of hydrogenating the aromatic hydrocarbon. The method according to claim 1, wherein the step of obtaining the hydrogenated oil comprises:
The pyrolysis heavy oil is hydrogenated in the presence of hydrogen under the conditions of hydrogen partial pressure of 0.7 to 20 MPa, LHSV of 0.05 to 2 h ^-1 , reaction temperature of 200 to 450 캜 and hydrogen / oil ratio of 100 to 2000 NL / L using a catalyst for hydrogenation treatment , And a step of distilling and separating the hydrogenated pyrolytic heavy crude oil. 6. The catalyst for hydrotreating according to claim 4 or 5, wherein the catalyst for hydrotreating is added to an inorganic carrier containing aluminum oxide in an amount of 10 to 30 mass% of at least one metal selected from Group 6 metals of the periodic table based on the total catalyst mass And 1 to 7% by mass of at least one metal selected from Group 8 to Group 10 metals of the Periodic Table. The method according to claim 6, wherein at least one metal selected from Group 6 metals of the periodic table is molybdenum and / or tungsten, and at least one metal selected from Group 8 to Group 10 metals of the periodic table is cobalt &Lt; / RTI &gt; and / or nickel. The process for producing an aromatic hydrocarbon according to claim 1, wherein the catalyst for producing monocyclic aromatic hydrocarbons comprises gallium and / or zinc. The process for producing an aromatic hydrocarbon according to claim 1, wherein the catalyst for producing the monocyclic aromatic hydrocarbon comprises phosphorus.

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